This proposal is in response to the limited competition RFA, issued by the NIDDK, soliciting cooperative agreement (U01) applications from investigators currently supported under RFA-DK-03-006 to continue the Longitudinal Assessment of Bariatric Surgery (LABS) Consortium to study bariatric surgery for an additional project period of five years. The site at the Neuropsychiatric Research Institute is enthusiastic about the possibility of continuing this research. Recent estimates suggest that 34% of the adult population in the United States is obese and the rate of obesity continues to increase. Bariatric surgery is the most effective treatment to accomplish sustained and significant weight loss for people with severe obesity. A number of studies have documented that the amount of weight loss following bariatric surgery is substantial, and associated with improvement or reversal in a variety of medical comorbidities including diabetes, sleep apnea, asthma, stress incontinence and infertility. This extension of the LABS Consortium would allow us to retain subjects to complete the longitudinal observation cohort database and maintain the infrastructure to support the conduct and analysis of LABS-3 substudies on the resolution of diabetes and psychosocial changes as well as various ancillary studies developed under the auspices of LABS. The NRI site, with the assistance of investigators at all the clinical sites and the DCC, has been instrumental in the development of the psychosocial, quality of life and eating behavior elements in LABS. Rates of psychopathology have been found to be quite high in bariatric surgery candidates. Also, various eating related behaviors such as binge eating and full syndrome binge eating disorder are quite common. Although, the data here are quite limited, there is a clear suggestion in the literature that although most psychopathology improves post-operatively more distally psychopathology may reemerge. Also, the reemergence of binge eating or out of control eating appears to be associated with less weight loss or more weight regain. The continuation of the LABS protocol would allow us to examine the relationships among such variables with adequate sample size for the first time. RELEVANCE (See instructions): This study is designed to examine the safety and efficacy of bariatric surgery in the treatment of severe obesity. Various outcomes of interest including medical and psychosocial outcomes are examined.